TUNIS, Tunisia - Unrest engulfed Tunisia as a popular rebellion that forced the president to flee turned to looting, and a deadly prison riot ended when the jail gates were opened, allowing about 1,000 inmates to go free.

Public television station TV7 broadcast phone calls from residents of working-class neighborhoods on the capital's outskirts, describing attacks against their homes by knife-wielding assailants.

The country's longtime autocratic ruler, President Zine El Abidine Ben Ali, fled the country Friday for Saudi Arabia following a popular uprising and deadly riots. The head of the Constitutional Court declared Saturday that Ben Ali has left office for good.

A new interim president, Fouad Mebazaa, was sworn in as chief of state Saturday. Mebazaa, the former president of the lower house of parliament, called for the formation of a "national unity government in the country's best interests."

Mebazaa has two months to organize new elections.

In his first televised address Mebazaa said that all political parties including the opposition will be consulted "without exception nor exclusion."

Anger over corruption and the lack of jobless ignited a month of protests, but Ben Ali's departure - a key demand of demonstrators - has not calmed the unrest. While the protests were mostly peaceful, after Ben Ali's departure rioters burned the main train station in Tunis and looted shops.

Sporadic gunfire was heard in the capital of Tunis Saturday. An Associated Press photographer saw soldiers try to stop looters from sacking a huge supermarket in the Ariana area, 20 miles north of the capital. Smoke billowed over the building as looters torched and emptied it.

The army fired warning shots to scare them away, to little avail.

Shops near the main bazaar were also looted.

A helicopter circled low over the capital, apparently acting as a spotter for fires or pillaging. Gunfire crackled anew Saturday morning.

A fire in a prison in the Mediterranean coastal resort of Monastir killed 42 people, coroner Tarek Mghirbi told The AP. Soldiers at the prison opened fire on the inmates after they rebelled Saturday, setting fire to mattresses and other objects.

The official estimates that five people were killed.

The official (speaking on condition of anonymity out of security fears) also said the prison director decided to open the prison gates to prevent further bloodshed. About 1,000 inmates were freed.

Thousands of tourists were evacuated from the Mediterranean nation known for its sandy beaches, desert landscapes and ancient ruins.

Saudi King Abdullah's palace confirmed Saturday that the ousted president and his family had landed in Saudi Arabia, saying the kingdom welcomed him with a wish for "peace and security to return to the people of Tunisia."

When Ben Ali left after 23 years of iron-fisted rule, Prime Minister Mohammed Ghannouchi stepped in briefly with a vague assumption of power that left open the possibility that Ben Ali could return. But Constitutional Council President Fethi Abdennadher said Saturday that Ben Ali has permanently vacated his position and lawmaker Mebazaa has up to 60 days to organize new elections.